发光二极管光谱测量中的杂散光与带宽校正  

Stray Light and Bandpass Correction in the Spectral Measurement for Light Emitting Diodes

作　　者：沈海平[1] 潘建根[2] 冯华君[1] 徐之海[1] 

机构地区：[1]浙江大学现代光学仪器国家重点实验室,浙江杭州310027 [2]杭州远方光电信息有限公司,浙江杭州310053

出　　处：《光谱学与光谱分析》2009年第6期1493-1497,共5页Spectroscopy and Spectral Analysis

基　　金：国家“863”高技术研究发展专项经费项目(2006AA03A173)资助

摘　　要：光谱仪的杂散光和带宽是LED光谱测量中比较重要的两个误差影响因素,为了得到更精确的测量结果,必须对杂散光和带宽影响进行校正。用He-Ne激光测出光谱仪的线扩展函数,在假设光谱仪是线性波长不变系统的前提下,构建杂散光分布函数矩阵,转化为杂散光校正矩阵,从而对所测信号进行杂散光校正;在三个波段内分别由光谱仪带宽函数计算带宽校正系数,将被测波长点及其邻近带宽波长点上的测量结果进行加权平均,从而得到带宽校正结果。将两种校正方法应用在一台多通道快速光谱仪上,测量各种颜色的LED,实验结果表明能有效地校正杂散光和带宽影响,色品坐标最大校正了(-0.003,0.007)。且该方法降低了应用成本,在保证精度的情况下简化了计算量,使得校正更易于实施。The present paper introduces the stray light and bandpass correction methods for spectrometers. The line spread function of spectrometer is characterized by a He-Ne laser. Assuming that the spectrometer is a wavelength invariable system, the stray light distribution matrix is constructed by the derived line spread functions. The stray light correction matrix is then derived by matrix conversion from the stray light distribution matrix. The measured signals of the spectrometer are finally multi plied by the stray light correction matrix to correct the stray light errors. The bandpass functions of the spectrometer are characterized in three different wavelength ranges, respectively. And then three groups of bandpass correction coefficients are calculated accordingly. The calculation is divided into several steps. Given the measurement results at the target wavelength position and the ones on the neighbor bandwidths, the bandpass correction results are obtained by weight averaging of them. The bandpass correction coefficients are used as the weights. The two correction methods are applied to a multi channel fast spectrometer to measure LEDs of different color. The results show that the stray light and the bandpass errors can be corrected effectively. The chromaticity coordinates of the LEDs are corrected by （-0. 003, 0. 007） for the maximum. Furthermore, the method introduced in this paper can reduce the application cost, simplify the calculation under a reasonable precision, and make the application of the correction easier.

关 键 词：发光二极管 光谱测量 杂散光 带宽 校正 

分 类 号：O433.1[机械工程—光学工程]